Implantable medical devices conventionally include a connector enclosure where the connectors mate to medical lead contacts and further include a can that houses the electrical circuitry. In these conventional devices, a top plate seals the can and exposes feedthrough pins that extend out of the can. The connector enclosure sits atop the top plate and receives the feedthrough pins where they connect to lead frame conductors that interconnect the feedthrough pins to the electrical connectors. Thus, during manufacturing, the feedthrough assembly is a part of the can assembly and the connector assembly is then added to complete the device, typically by creating the electrical connections for the connector assembly and then forming the connector enclosure over the connections using a polymer.
Within the can of the convention medical device, the feedthrough pins pass through and are bonded to a filter capacitor that provides a capacitive coupling to the can to filter out unwanted electromagnetic interference signals from entering into the device. The feedthrough pins including a pin dedicated for establishing an electrical ground for the electrical circuitry within the can would then be laser welded to a feedthrough contact. A flexible circuit portion interconnects the feedthrough contact to the circuit board that contains the electrical circuitry of the device.
This conventional approach has less appeal as device designs continue to get smaller. The amount of space required to bond the feedthrough pins to the filter capacitor and then bond the feedthrough pins to the underlying feedthrough contact limit the amount of miniaturization that may occur in the area of the feedthrough connections within the can. Furthermore, these feedthrough manufacturing operations require valuable time and resources to accomplish. In some cases, even the flexible circuit may be an undesirable cost in terms of resources and space requirements.